The signs and symptoms of tubo-ovarian abscess (TOA) are the same as with pelvic inflammatory disease (PID) with the exception that the abscess can be found with magnetic resonance imaging (MRI), sonography and x-ray. It also differs from PID in that it can create symptoms of acute-onset pelvic pain. Typically this disease is found in sexually active women but sexually inexperienced, virginal girls have rarely been found with this infection.

Tubo-ovarian abscesses (TOA) are one of the late complications of pelvic inflammatory disease (PID) and can be life-threatening if the abscess ruptures and results in sepsis. It consists of an encapsulated or confined 'pocket of pus' with defined boundaries that forms during an infection of a fallopian tube and ovary. These abscesses are found most commonly in reproductive age women and typically result from upper genital tract infection. It is an inflammatory mass involving the fallopian tube, ovary and, occasionally, other adjacent pelvic organs. A TOA can also develop as a complication of a hysterectomy.

Patients typically present with fever, elevated white blood cell count, lower abdominal-pelvic pain, and/or vaginal discharge. Fever and leukocytosis may be absent. TOAs are often polymicrobial with a high percentage of anaerobic bacteria. The cost of treatment is approximately $2,000 per patient, which equals about $1.5 billion annually. Though rare, TOA can occur without a preceding episode of PID or sexual activity.

Symptoms can vary. Some patients have lower often recurring abdominal pain or pelvic pain, while others may be asymptomatic. As tubal function is impeded, infertility is a common symptom. Patients who are not trying to get pregnant and have no pain, may go undetected.

Endometriosis, ruptured appendicitis, and abdominal surgery sometimes are associated with the problem. As a reaction to injury, the body rushes inflammatory cells into the area, and inflammation and later healing result in loss of the fimbria and closure of the tube. These infections usually affect both fallopian tubes, and although a hydrosalpinx can be one-sided, the other tube on the opposite side is often abnormal. By the time it is detected, the tubal fluid usually is sterile, and does not contain an active infection. (Not symptoms)

A hydrosalpinx is a distally blocked fallopian tube filled with serous or clear fluid. The blocked tube may become substantially distended giving the tube a characteristic sausage-like or retort-like shape. The condition is often bilateral and the affected tubes may reach several centimeters in diameter. The blocked tubes cause infertility.

A fallopian tube filled with blood is a hematosalpinx, and with pus a pyosalpinx.

Hydrosalpinx is a composite of the Greek words ὕδωρ (hydōr – "water") and σάλπιγξ (sálpinx – "trumpet"); its plural is "hydrosalpinges".